Exosomes are small vesicles containing proteins, nucleic acids and lipids, which are associated with intercellular communication and regulation of the tumor microenvironment, thus becoming an emerging noninvasive marker for early cancer diagnosis. Current techniques for exosome analysis are complex, time-consuming and costly. In recent years, surface enhanced Raman scattering (SERS) has shown great potential in biomedical field due to its high sensitivity, simple sample preparation, rapid and noninvasive advantages. In this review, the exosomes are introduced and the merits and drawbacks of the main detection methods are compared. The characteristics of SERS as well as its advantages in exosome detection are described, with emphasis on the application progress of label-free and label SERS in exosome detection. Studies have shown that SERS-based exosome detection technology is expected to become a noninvasive, convenient and accurate new method for clinical diagnosis.